1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * psci_test - Tests relating to KVM's PSCI implementation.
4 *
5 * Copyright (c) 2021 Google LLC.
6 *
7 * This test includes:
8 * - A regression test for a race between KVM servicing the PSCI CPU_ON call
9 * and userspace reading the targeted vCPU's registers.
10 * - A test for KVM's handling of PSCI SYSTEM_SUSPEND and the associated
11 * KVM_SYSTEM_EVENT_SUSPEND UAPI.
12 */
13
14 #include <linux/kernel.h>
15 #include <linux/psci.h>
16 #include <asm/cputype.h>
17
18 #include "kvm_util.h"
19 #include "processor.h"
20 #include "test_util.h"
21
22 #define CPU_ON_ENTRY_ADDR 0xfeedf00dul
23 #define CPU_ON_CONTEXT_ID 0xdeadc0deul
24
psci_cpu_on(uint64_t target_cpu,uint64_t entry_addr,uint64_t context_id)25 static uint64_t psci_cpu_on(uint64_t target_cpu, uint64_t entry_addr,
26 uint64_t context_id)
27 {
28 struct arm_smccc_res res;
29
30 smccc_hvc(PSCI_0_2_FN64_CPU_ON, target_cpu, entry_addr, context_id,
31 0, 0, 0, 0, &res);
32
33 return res.a0;
34 }
35
psci_affinity_info(uint64_t target_affinity,uint64_t lowest_affinity_level)36 static uint64_t psci_affinity_info(uint64_t target_affinity,
37 uint64_t lowest_affinity_level)
38 {
39 struct arm_smccc_res res;
40
41 smccc_hvc(PSCI_0_2_FN64_AFFINITY_INFO, target_affinity, lowest_affinity_level,
42 0, 0, 0, 0, 0, &res);
43
44 return res.a0;
45 }
46
psci_system_suspend(uint64_t entry_addr,uint64_t context_id)47 static uint64_t psci_system_suspend(uint64_t entry_addr, uint64_t context_id)
48 {
49 struct arm_smccc_res res;
50
51 smccc_hvc(PSCI_1_0_FN64_SYSTEM_SUSPEND, entry_addr, context_id,
52 0, 0, 0, 0, 0, &res);
53
54 return res.a0;
55 }
56
psci_features(uint32_t func_id)57 static uint64_t psci_features(uint32_t func_id)
58 {
59 struct arm_smccc_res res;
60
61 smccc_hvc(PSCI_1_0_FN_PSCI_FEATURES, func_id, 0, 0, 0, 0, 0, 0, &res);
62
63 return res.a0;
64 }
65
vcpu_power_off(struct kvm_vcpu * vcpu)66 static void vcpu_power_off(struct kvm_vcpu *vcpu)
67 {
68 struct kvm_mp_state mp_state = {
69 .mp_state = KVM_MP_STATE_STOPPED,
70 };
71
72 vcpu_mp_state_set(vcpu, &mp_state);
73 }
74
setup_vm(void * guest_code,struct kvm_vcpu ** source,struct kvm_vcpu ** target)75 static struct kvm_vm *setup_vm(void *guest_code, struct kvm_vcpu **source,
76 struct kvm_vcpu **target)
77 {
78 struct kvm_vcpu_init init;
79 struct kvm_vm *vm;
80
81 vm = vm_create(2);
82
83 vm_ioctl(vm, KVM_ARM_PREFERRED_TARGET, &init);
84 init.features[0] |= (1 << KVM_ARM_VCPU_PSCI_0_2);
85
86 *source = aarch64_vcpu_add(vm, 0, &init, guest_code);
87 *target = aarch64_vcpu_add(vm, 1, &init, guest_code);
88
89 return vm;
90 }
91
enter_guest(struct kvm_vcpu * vcpu)92 static void enter_guest(struct kvm_vcpu *vcpu)
93 {
94 struct ucall uc;
95
96 vcpu_run(vcpu);
97 if (get_ucall(vcpu, &uc) == UCALL_ABORT)
98 REPORT_GUEST_ASSERT(uc);
99 }
100
assert_vcpu_reset(struct kvm_vcpu * vcpu)101 static void assert_vcpu_reset(struct kvm_vcpu *vcpu)
102 {
103 uint64_t obs_pc, obs_x0;
104
105 vcpu_get_reg(vcpu, ARM64_CORE_REG(regs.pc), &obs_pc);
106 vcpu_get_reg(vcpu, ARM64_CORE_REG(regs.regs[0]), &obs_x0);
107
108 TEST_ASSERT(obs_pc == CPU_ON_ENTRY_ADDR,
109 "unexpected target cpu pc: %lx (expected: %lx)",
110 obs_pc, CPU_ON_ENTRY_ADDR);
111 TEST_ASSERT(obs_x0 == CPU_ON_CONTEXT_ID,
112 "unexpected target context id: %lx (expected: %lx)",
113 obs_x0, CPU_ON_CONTEXT_ID);
114 }
115
guest_test_cpu_on(uint64_t target_cpu)116 static void guest_test_cpu_on(uint64_t target_cpu)
117 {
118 uint64_t target_state;
119
120 GUEST_ASSERT(!psci_cpu_on(target_cpu, CPU_ON_ENTRY_ADDR, CPU_ON_CONTEXT_ID));
121
122 do {
123 target_state = psci_affinity_info(target_cpu, 0);
124
125 GUEST_ASSERT((target_state == PSCI_0_2_AFFINITY_LEVEL_ON) ||
126 (target_state == PSCI_0_2_AFFINITY_LEVEL_OFF));
127 } while (target_state != PSCI_0_2_AFFINITY_LEVEL_ON);
128
129 GUEST_DONE();
130 }
131
host_test_cpu_on(void)132 static void host_test_cpu_on(void)
133 {
134 struct kvm_vcpu *source, *target;
135 uint64_t target_mpidr;
136 struct kvm_vm *vm;
137 struct ucall uc;
138
139 vm = setup_vm(guest_test_cpu_on, &source, &target);
140
141 /*
142 * make sure the target is already off when executing the test.
143 */
144 vcpu_power_off(target);
145
146 vcpu_get_reg(target, KVM_ARM64_SYS_REG(SYS_MPIDR_EL1), &target_mpidr);
147 vcpu_args_set(source, 1, target_mpidr & MPIDR_HWID_BITMASK);
148 enter_guest(source);
149
150 if (get_ucall(source, &uc) != UCALL_DONE)
151 TEST_FAIL("Unhandled ucall: %lu", uc.cmd);
152
153 assert_vcpu_reset(target);
154 kvm_vm_free(vm);
155 }
156
guest_test_system_suspend(void)157 static void guest_test_system_suspend(void)
158 {
159 uint64_t ret;
160
161 /* assert that SYSTEM_SUSPEND is discoverable */
162 GUEST_ASSERT(!psci_features(PSCI_1_0_FN_SYSTEM_SUSPEND));
163 GUEST_ASSERT(!psci_features(PSCI_1_0_FN64_SYSTEM_SUSPEND));
164
165 ret = psci_system_suspend(CPU_ON_ENTRY_ADDR, CPU_ON_CONTEXT_ID);
166 GUEST_SYNC(ret);
167 }
168
host_test_system_suspend(void)169 static void host_test_system_suspend(void)
170 {
171 struct kvm_vcpu *source, *target;
172 struct kvm_run *run;
173 struct kvm_vm *vm;
174
175 vm = setup_vm(guest_test_system_suspend, &source, &target);
176 vm_enable_cap(vm, KVM_CAP_ARM_SYSTEM_SUSPEND, 0);
177
178 vcpu_power_off(target);
179 run = source->run;
180
181 enter_guest(source);
182
183 TEST_ASSERT_KVM_EXIT_REASON(source, KVM_EXIT_SYSTEM_EVENT);
184 TEST_ASSERT(run->system_event.type == KVM_SYSTEM_EVENT_SUSPEND,
185 "Unhandled system event: %u (expected: %u)",
186 run->system_event.type, KVM_SYSTEM_EVENT_SUSPEND);
187
188 kvm_vm_free(vm);
189 }
190
main(void)191 int main(void)
192 {
193 TEST_REQUIRE(kvm_has_cap(KVM_CAP_ARM_SYSTEM_SUSPEND));
194
195 host_test_cpu_on();
196 host_test_system_suspend();
197 return 0;
198 }
199